The present invention relates to thermoplastic films, more particularly to packaging films, especially films useful in packaging food products such as poultry.
In the packaging of products, especially food products such as poultry, PVC (polyvinyl chloride) has been a traditional packaging material.
PVC suffers from several deficiencies, including environmental concerns about possible migration of vinyl chloride monomer residuals, as well as plasticizer, into a food product packaged with PVC. PVC sometimes has lower abuse resistance and poorer memory than alternative packaging materials.
More recently, olefinic materials such as SSD film and SES film provided by the Cryovac Division of W. R. Grace & Co.-Conn. have proven useful in packaging poultry. These olefinic materials have excellent physical properties, including good memory. By "memory" is meant the propensity of the packaging material, after being stretched over for example a trayed food product, to substantially return to its original dimensions after product settling. Also, it refers to the tightness of the trayed package during storage and distribution. Films with poor memory tend to show slackness or looseness in the packaging film overwrap of a trayed food package.
It is desirable, especially when packaging "high profile" foods, i.e. foods that project above the edge of the tray, such as whole poultry, or poultry parts, to have films with even better memory. This would then allow for product settling while still substantially maintaining the tight package appearance.
The present invention solves this need by a multilayer oriented film which includes a thermoplastic polyolefin (TPO) in the film structure.